Seymour pratt



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TO ALL WIIOM IT MAY CONOERN:

Be it known that I, SEYMOUR PRATT, of Fayetteville, in the county of Onondaga, and State of New York, havev invented a. new and improved Roofing; and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled iu the art to make and use the same, reference being had to the accompanying drawings, forming part of thisspecification.

This invention consists in constructing a roofing of hydraulic cement mixed with lime and sand, this` composition beingr pressed into square or other proper-shaped blocksor tiles, and laid, when in a set or dried, state, upon boards or luth nailed to the rafters. The cementblocks or tiles are, when laid upon the boa-rds or; laths, cemented together by and laid upon the same material in a plastic state as the blocks or tiles are made"t of. Invthe accompanying sheet of drawings- Figure 1 is a section of a portion of a roof constructed or formed according to my invention.

Figure 2, a plan .or top view of the same.

Similar letters of reference indicate like parts. f

Azrepresents one of the rafters of a roof, and B represents boards attached 'thereto by nails. In lieu offv boards laths may be used, and the luth I consider preferable, as, being:r narrow and thin, they would not be so liable to affect the cement of the rooting by shrinkage. 'lho boards or laths B are covered with a layer ot cement, O, laid on in a plastic state, the cement beingr mixed with lime and sand in about the same proportion as masons mix cement for `cisterns and masonry generally, to wit, one-fourth (if) part hydraulic cement and three-fourths of lime and sand. On this cement bed- C tiles D are laid, which may be about afoot square and an inch thick. I do not, however, confine myself to these proportions. These tiles D are constructed of` hydraulic cement and lime and sand about in the proportions-above specified, and they are pressed and moulded` llike brickspand are allowed to become perfectly' dryand hard before being used. rIhe edges of these tiles when laid are joined by the fresh or softcement the saine' as C. By this mea-ns I obtain a cheap and durable vroof. Hydraulic Cement and lime and sand mixed in abouti-'the proportions specified, and allowed to set of'lry gradually, forms a very hard material like stone. A roofing laid Wholly with cement in a plastic sta-tc would not answer a good purpose, as it would dry too rapidly under the influence of the sun and wind, and when thus dried cannot be like powder, having but little tenacity. The plastic bed C, however., being covered by the tiles D, is prevented from drying rapidly, and consequently will set slowly with the tiles embedded in it, thc whole eventually forming a very hard and durable mass. The layer of tiles at the sides of the root` may be kept in place by metal strips a, or wooden cleats may be used instead.

Having thus described my invention, I claim as new, and desire to secure 4by Letters Patent- A rooting composed of the tiles D, constructed as described, placed on a bed of cement, C, laid on the boards or laths B, substantially as herein shown and described. I l

I vThe above specification of my invention signed by me this 16th day of January, 1867.

I SEYMOUR PRATT.

Witnesses:

WM. F. MCNAMARA, ALEX. F. ROBERTS. 

